DR John Snow and Cholera
DR John Snow and Cholera
DR John Snow and Cholera
cholerae).
Symptoms include chronic diarrhoea, low blood pressure and dehydration. Infected patients can die within 3 hours if left untreated.
In 1854, there was a cholera outbreak in London. It had devastating outcomes with over 500 fatalities.
Nearly all families lost at least one member (regardless of socioeconomic class).
By talking to local residents, Snow identified the source of the outbreak as the public water pump on Broad Street.
Snow later used a spot map to illustrate how cases of cholera were centred around the pump.
Snow concluded that all the people infected with cholera had drunk water collected from the Broad Street well. It was later discovered that a leaking cess pit containing sewage was only 3ft away from the well and was contaminating the water.
Snow's studies of the pattern of the disease were convincing enough to persuade the local council to disable the well pump by removing its handle.
This caused the number of cholera cases to decrease rapidly.